Hitch construction



L. L. HYLER HITCH CONSTRUCTION Dec. 2.6, 1950 3 Sheets-Sheet, 1

Filed July 22, 1946 D ec. 26, 1950 L.. HYLER 2,535,927

HITCH CONSTRUCTIGN Filed July 22, 194e s sheets-sheet 2 M55 t @j/'44, @ik vM/yw; w

Dec. 26, 1950 L. l.. HYLER 2,535,927

\ HITCH CONSTRUCTION Filed July 22, 1946 3 Sheets-Sheet 3 Patented Dec. 2.6, 1950 UNITED STAT EIS! PATENT FFICE HITGH CGNSTEUGTIGN Loiell L. Hyler, Cedar: Rapids, iowa, assigner to.- La.` Plantehoate Manufacturing Co., inc., Cedar Rapids, iowar a corporation of lielaware Aflpplioator July 22, 1946, SerialiNovAB fi Eiaians.

'llhis invention relates tov vehicles. of the type: comprising a trailer and a prime` mover, more particularly to hitch. constructions for coi'u'iect.-`

shown and? described in connection with hitch constructions for Vehicleslconiprising. two wheel prime mover andi an-earth-moving trailer vehicle, such as a scraper, for excavating; transporting and-discharging earth and similar materials. The advantagesot employing two -Wheel prime "movers inl earth-moving apparatus or thisltype'have heretofore been recognized`,. particularly Where it is necessary or desirable to` transport the material substantial; distancesibetweenthe place of exea--` vation and` the place of discharge. The high speed operation which is obtainable when employ-ing twovvvheel' prime movers as compared" to the speeds obtainable when employing track-laying or crawler-type tractors as; the prime mover; isan important factor` ini economy of' operation and enablessubstanti'al reductions in the. time required for completing` any particular earthmoving joli; However; difliculties have* been er1-- countered in providing simple and satis-factory hitch mechanisms capable of withstanding the heavy strainsencountered and of supporting the loads involved-1 in moving` large quantitiesfot earthover uneven and variable terrain.

In prior earth-moving vehclesfof the type above indicated; hitch constructions` have been emplayed which serve as part of the steeringinechanism and'includevarious gears; sprockets, chains and levers for effecting steering control of the hitch mechanism. Such prior constructions have involved excessive expense: and:` dliilicul'ties` in manufacture, andf have been a source or trouble' inoperation tln'ougl'i4 breakage and excessivewear of the parts dueto insufficient bearing surfaces and improper design. Accordingly, it isV a fur-- ther ohiectof` thisinvention tolprovide a troublefree hitch construction for connecting a prime mover andi a trailer in steerable relation, which is capable of ready' assembly and of operation over long periods under heavy loads without breakage or excessive. Wear.

In.l carrying out the; invention. in one forrn` a vehicle including a trailer and a prime moversis provided with` a` hitch construction` comprising. an upstanding element mounted` onV the: prime.v mover yin. nonrotatahle relation:

rotation relative; to the prime mover, the hollow` 5L `memoir including; means extending outvfafrdly` therefromand terminating inV an` annular iangcf` slidahly supported in hearing means carried hy the primeflnover and enga-gine` the upper and'.` lower surfaces of the flange. in ioadtransmittinga-g luqrelation at spaced points: about the periphery ot the flange.`

More particularly., the upstanding. element isf, mounted` on the` prime mover` for pivotal relationo` ina plane substantially at right angles tothe lon-f;

151; gitudinal axis ot the primeindo-verf,` and the annue lar ange, which is suitably hardened, is' con-ii nested to the hollow member by a conical. skirt portion,` the: bearing means for' engaging the.,

flange: being positioned: on the longitudinal` axis7 Fig. 1 is an elevationallvievr of: a: vehicle'whenein the two-whee1 prime` mover and the trailer-aref" connected by a hitch construction embodying` the present invention;

constructionxemnloyed in thevehic e oi Fig. l;

vliigu 31 is a fragmentary somewhat diagram-= matic perspective View' of the: hitch construction.. .1.o shown in 2;.rportionseof the prime mover ando the trailer vehicle being; omitted` in order more;

clearly to illustratethefstructure of the hitch;`

4 isa detail` view partly in section. taken'4 alonetheline l-4 of Fig. 2i;

taken along. the.` line 5-5 of Fig. 2l; and

Figs.. densi 7: are detail sectional views taken;V along the.w lines two and in-Tl, respectively; ot 1;

thereto, and a hollovvq4 member' secured in nonrotatable relation to the. trailer is journaled-.on the opstanding element for Y* Fig. 2 is a` vertical sectional view on a 1arger.; scale taken through the centerline: or. thehitch` 1 fFig. 5 is` ai fragmentary View partly in4 section` Vleferring; now` to: the` drawings, the invention.` is shown as embodied in.A anearthfmovingvehiclelg comprising a two-Wheel prime mover unit infancia a two-Wheel scraper on trailer vehicle* l lof al type: welbknovmiin theart.. Thescraper MJisvprovidedf-r Miet its forwaxid end witha` conventional gooseneck@ 3 I2 adapted to be secured to a hitch construction I3 embodying the present invention, whereby the traction wheels lll of the prime mover support a portion of the weight of the scraper and the Weight of the material carried thereby. It will be seen that both the prime mover IIJ and the trailer vehicle II are of the unstable type adapted to form a stable vehicle only when connected tgether through the yoke connection and the hitch construction i3.

As shown best in Figs. 2 and 6, the hitch construction embodying the invention includes a ball-like support I5 mounted on a portion I5 of the prime mover substantially on the longitudinal center line of the prime mover and substantially over the axis of rotation of the wheels I4. Cooperating with the ball-like support I5 is a socket I1 to which is rigidly secured an upstanding element or post I8. The socket I1 is provided with square or otherwise noncircular apertures I9 in opposite sides thereof adapted to receive the correspondingly formed heads 20 of a pair of pins 2| having shank portions which extend into suitable cylindrical apertures in the ball-like member i5. Inasmuch as the shank portions of the pins 2I are rotatable in the apertures in the ball support I5, the socket I1 and the post I8 are secured to the prime mover for pivotal movement in a plane at right angles to the longitudinal center line of the prime mover but are locked by the pins 2I against rotation about a vertical axis with respect to the prime mover, the square heads 20 providing large flat bearing surfaces for transmitting to the prime mover any turning movement exerted by the post I8.

Surrounding the post i8 and engaging the outer periphery of the socket I1 is a hollow member or pedestal 22 which is provided with an upwardly inclined hollow arm including top and bottom plates 23 and 24 connected by side plates 25, which hollow arm terminates in a vertically disposed mounting plate 26 adapted to be secured by suitable screws and bolts 21 to a cooperating plate 23 carried on the forward end of the gooseneck i2. As shown best in Figs. 2 and 5, the mounting plate 2E is provided with a key 29 preferably in the shape of a cross adapted to extend through a similarly cross-shaped slot in the plate 28 in order properly to position the connecting plates 25 and 28 relative to each other when the prime mover and the scraper are connected together.

Although a rather large bearing surface is provided by the construction heretofore described between the hollow member 22 and the socket I1 on which the post I8 is mounted, the extremely heavy stresses and loads encountered during operation of a scraper vehicle of the type herein disclosed requires further support of the hollow member 22 which is rigidly connected to the trailer or scraper vehicle II so as to adequately support the front end of the trailer vehicle while permitting relative turning movement between the trailer and the prime mover to eifect steering of the vehicle. Accordingly, as shown best in Figs. 2, 3 and 6, a hardened annular member or flange 38 is provided surrounding the pedestal 22 adjacent the lower end thereof which annular member is rigidly connected to the pedestal 22 by a pair of substantially frustoconical skirt portions 3I and 32. Although this supporting structure may be fabricated in any desired manner, the skirt portions 3I and 32 are preferably welded at their upper ends to the 4 pedestal 22 and at their lower ends to the hardened annular member 33 so as to provide a rigid structure.

In order to support the annular member in load-transmitting relation to the prime mover while at the same time permitting relative pivotal movement between the prime Vmover and the trailer vehicle in planes transverse to the longitudinal axis thereof, suitable bearing units 33 and 34 are provided mounted on the prime mover on substantially the center line thereof on opposite sides of pedestal 22 so as to engage the hardened annular member 38 at peripherally spaced points. The bearing units 33 and 34, although mounted in inverse relation, are identical in construction, and only the bearing unit 33 will be described in detail, similar reference numerals being used to indicate like parts in the two b earing units.

Referring to Figs. 2 and 7, the bearing unit 33 comprises a spud or supporting member 35 rigidly secured to and extending upwardly from a portion I6 of the frame of the prime mover, which Spud 35 is provided with an aperture 36 for receiving a pin 31. Surrounding the spud 35 in pivotal relation thereto is a housing comprising spaced apart side plates 39 connected together by a top member 4I) and by front and rear plates 4I and 42 respectively, the front and rear plates 4I and 42 being suitably apertured for receiving the extending ends of the pin 31, the housing being locked to the pin 31 by means of a suitable bolt 43 which extends through cooperating apertures in the pin 31 and the back plate of the housing.A It will thus be apparent that the housing is supported on the Spud 35 for pivotal movement in planes substantially at right angles to the axis of the prime mover.

Extending forwardly from the front plate 4I of the bearing housing are horizontally disposed spaced apart plates 44 to which are secured by suitable bolts 45 wear plates 4E adapted to engage the upper and lower surfaces of the hardened annular flange 38. It will be understood, of course, that the wear plates 46 may be suitably shimmed to take up any wear occurring between these plates and the flange so as to maintain at all times the proper load-transferring relation between the hardened flange 30 andthe bearing structure 33. As previously indicated, bearing unit 34 isV inverted with respect to the bearing unit 33, and as shown best in Figs. 2 and 3 is secured to a suitable transverse beam 48 which extends across and forms a part of the frame of the prime mover IIJ. Inasmuch as the hardened annular ange 30 is disposed in the same horizontal plane as the pins 2I which connect the socket I1 to the ball support I5, and since the pins 31 in the bearing units 33 and 34 are in alignment with the pins 2I, the hardened annular flange and the skirt portions 3| and 32, while slidably supported in rotatable relation to the wear plate 46, are capable of tilting movement with the pedestal 22 and the post I8 as indicated by the broken lines 49 and 5! in Fig. 7.

In order to provide for proper lubrication of the Various bearing surfaces, the ball support I5 is provided, as shown, with a lubricating duct 5I which communicates with a central chamber 52 leading to the space 53 provided between the ball support I5 and the socket I1 by the flattened upper surface of the ball support I5. Thus grease or other suitable lubricant forced into the grease duct 5I will find its way into the space 53 and from there will travel downwardly around the atentar.

outer periphery ofthe ball to forma lubricating nlm between the ball and socket. Lubrication of the .bearingsurface between the pedestal 22 and the outer periphery of the socket il may be achieved merely by introducing a :suitable `lubricant through the open upper end of the pedestal 22, which open upper end may be provided with a suitable protecting cover if desired.

Lubrication of the hardened annular flange 3i) and protection of the flange from the abrasive action of dust and `similar particles is `accomplished by providing `suitable `sector-shaped dust :shields and lubricant containers 54 `and 55 (Fig. 3) which extend .between the bearing units 33 and 35 so as to substantially enclose the ange 30. rIhese dust shields 54 Iand `55 are substantially U-shaped in cross section with the top and bottom walls tapering inwardly so as to frictionally engage the flange 3|] andsuitable grease fittings 55 are provided for introducing ylubricant into the space between the shields Strand 5.5:andthe flange 3-0.

It will now be apparent that hitch structures embodying the present invention provide a `compact and ruggedsteerable connection between the prime mover and the trailer vehiclaand in order to effect power steering of the prime mover any suitable power operating means may be employed for effecting rotation of the post i8 so as to turn the prime mover relative to the trailer vehicle. In the embodiment of the invention shown in the drawings, the means for rotating the post i8 to eieot steering is illustrated as constituting hydraulic means of the type described and claimed in a copending application of Harvey W. Rockwell, Serial No. 685,317, led July 22, 1946, now Patent No. 2,521,652, granted Sept. 5, 1950, entitled Steering Mechanisms, which application is assigned to the same assignee Aas the present in vention., The said Rockwell application discloses a modiiied vform of hitch construction embodying if the present invention wherein the hydraulic operator or ram is mounted directly on and forms a part of the hollow member or pedestal to which the trailer vehicle is secured.

In the form of invention herein shown, however, the hydraulic operator comprises a housing rigidly secured to the mounting plate 26 to which the pedestal member 22 is likewise secured so that the same rigid relation is achieved as in the said Rockwell application. Referring particularly to Figs. 2, 4 and 5 the hydraulic operating mechanism comprises a housing which includes a cylindrical side wall member i3d provided with inwardly projecting opposed wall portions 5! and 62 (Fig. 5) and cooperating top and bottom plates 53 and 64, respectively. Suitable bolts 55 are arranged to secure the side wall portion and the top and bottom plates together in fluid-tight relation so as to provide a hydraulic cylinder, and extending portions 5E on the top and bottom plates 63 and 84 are secured by bolts 57 to supporting plates 68 which extending outwardly from the mounting plate 25, whereby the lluid-tight housing is secured in rigid relation to the mounting plate 25 and the pedestal 22.

As shown best in Fig. 2, the post i8 extends through suitable apertures in the top and bottom plates IES and 64, suitable scaling means 65 and 10 being provided as is more fully described in the said copending Rockwell application, and the portion of the post i3 extending through the housing is splined as indicated by the reference numeral 1l for cooperatively engaging the hub portion of a double-acting vane 12 (Fig. 5). The inwardly projecting wall portions Sl and 'B2 are provided with ,suitable sealing members 'I3 which: engage the periphery `of the hub of the vane member l2, and the outer ends of the vanes arev provided with sealing members 'M 4for similarly engaging the 'internal walls of the side wall member 65. Thus a plurality of fluid-tight chambers l5, 1.6, .11 and 118 are provided for receiving hydraulic medium under pressure in `order to effect rotation yof the vane member l2 to drive the steering element or post t3, and the inwardly projecting wall portions t! and 52 `are provided with suitable vducts 1S, 8e, 8| and 82 through which the duid pressure medium may be supemay be supplied through the conduit 8B to the chambers 'i6 and 18 to `effect rotation of the vane member 12 in a clockwise direction.

Any :suitable means may be employed for selectively applying fluid pressure to the hydraulicoperating unit thus far described, and for the purposes of the present -invention it is not believed necessary to .illustrate or describe in `detail the particular control means described and claimed in the aforesaid Rockwell application. For purposes of completeness, however, it should be pointed out that the instrumentality illustrated in Figs. 3, a 'and 5 as being mounted directly over the uid operator comprises a hydraulic followup mechanism adapted to be driven by the rotatable post i8 to effect accurate `control of the steering. This follow-up mechanism includes a stub shaft 9D 'carrying a gear 9i adapted to mesh with a rack 92 having pistons S3 carried on the opnosite ends thereof 4adapted to move 'within a cylinder 94 for producing differential pressures corre.

sponding to movements of the steering post I8. The differential pressures thus produced are transmitted through suitable conduits 95 communicating with opposite ends of the cylinder 94 and are utilized in accordance with the invention of the aforesaid Rockwell application to control the supply of fluid pressure to the vane type fluidoperating means heretofore described.

While I have shown a particular embodiment of my invention, it will be understood, of course, that I do not wish to be limited thereto since many modifications may be made, and I, therefore, contemplate by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

, l. In a vehicle including a trailer and a prime mover, a hitch comprising an upstanding element mounted on said prime mover in nonrotatable relation thereto, a hollow member secured in nonrotatable relation to said trailer and journaled on said element for rotation relative to said prime mover, rigid means extending outwardly from said hollow member and terminating in a hardened annular flange, spaced apart bearing means on said prime mover independent of and remote from said element including replaceable wear plates engaging the upper and lower surfaces of said ange in load-transmitting relation assise??l at spaced points about the periphery thereof,'and segmental cover members of substantially U- shaped cross section extending between said bearing means and encompassing said flange to form a continuous dust shield and lubricant container therefor.

2. In a vehicle including a trailer and a prime mover, a hitch comprising an upstanding element mounted on said prime mover in nonrotatable relation thereto, a hollow member secured in nonrotatable relation to said trailer and journaled on said element for rotation relative to said prime mover, a substantially conical rigid skirt extending outwardly from said hollow member and terminating in an annular hardened flange, spaced apart bearing means on said prime mover independent of said element and in spaced relation thereto for slidably engaging the upper and lower surfaces of said flange in load transmitting relation at spaced points about the periphery thereof, and segmental cover members of substantially U-shaped cross section encompassing the portions of said flange between said bearing means and permitting sliding movement of said flange therein to form a continuous dust shield and lubricant container for said flange.

3. In a vehicle including a trailer and a prime mover, a hitch comprising an upstanding element pivotally mounted on said prime mover in nonrotatable relation thereto, a hollow member secured in nonrotatable relation to said trailer and journaled on said element for rotation relative to said prime mover, rigid means extending outwardly from said hollow member terminating in a hardened annular flange, a pair of bearings disposed on opposite sides of said element and including wear plates slidably engaging the upper and lower surfaces of said ilange to support said hollow member for said relative rotation, means pivotally mounting said bearings on said prime mover to permit pivotal movement of said ange and said hollow member with said element, and segmental cover members of substantially U- shaped cross section encompassing the portions of said flange between said bearings and permitmeans extending through said apertures for lock ing said element against rotation relative to saidprime mover While permitting pivotal movement at right angles to said pin means, a hollow pedestal surrounding said element and secured in nonrotatable relation to said trailer, a rigid sube stantially conical skirt extending outwardly from' said pedestal and terminating in an annular flange disposed in a plane coincident with the axis J of said pin means, a pair of bearings disposed on opposite sides of said pedestal and engaging said flange to support said pedestal for rotation rela-- tive to said prime mover, means including pins coaxial with said pin means mounting said bearings for pivotal movement to permit pivoting of said pedestal with said member, segmental cover members of substantially U-shaped cross section extending between said bearings and embracing said flange to provide a continuous 'dust shield and lubricant container therefor, and means for effecting relative rotation betweensaid element and said pedestal to steer said vehicle.

LOIELL L. HYLER.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,361,935 French Nov. 7, 1944: 2,368,202 Clark Jan. 30, 1945 2,399,278 Le Tourneau Apr. 30, 1946- 2,400,218

Akers May i4, 1946 

